document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=723156>Question 723156</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A plane travels 100 mph in still air. It travels 240 miles into the wind and<BR>\n" );
document.write( "240 miles with the wind in a total time of 5 hours. Find the wind speed. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #443065 by </B><A HREF=/tutors/aboutme.mpl?userid=josmiceli><B>josmiceli(19441)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=josmiceli><IMG SRC=http://www.algebra.com/images/aboutme-small.gif BORDER=0 alt=\"About Me\" VALIGN=MIDDLE></A>&nbsp;<IMG SRC=http://www.algebra.com/cgi-bin/show-face.mpl?user=josmiceli><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=443065\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Let <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+w+ ALIGN=MIDDLE  ALT=\"+w+\"   DISABLED_style= \"max-width:90%; height:auto;\" > = the wind speed in mi/hr<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+100+%2B+w+ ALIGN=MIDDLE  ALT=\"+100+%2B+w+\"   DISABLED_style= \"max-width:90%; height:auto;\" > = the plane's speed going with the wind in mi/hr<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+100+-+w+ ALIGN=MIDDLE  ALT=\"+100+-+w+\"   DISABLED_style= \"max-width:90%; height:auto;\" > = the plane's speed going against the wind in mi/hr<BR>\n" );
document.write( "Let <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+t+ ALIGN=MIDDLE  ALT=\"+t+\"   DISABLED_style= \"max-width:90%; height:auto;\" > = plane's time going against the wind in hrs<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+5+-+t+ ALIGN=MIDDLE  ALT=\"+5+-+t+\"   DISABLED_style= \"max-width:90%; height:auto;\" > = planes time going with the wind in hrs<BR>\n" );
document.write( "----------------<BR>\n" );
document.write( "Equation going against the wind:<BR>\n" );
document.write( "(1) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+240+=+%28+100+-+w+%29%2At+ ALIGN=MIDDLE  ALT=\"+240+=+%28+100+-+w+%29%2At+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Equation going with the wind:<BR>\n" );
document.write( "(2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+240+=+%28+100+%2B+w+%29%2A%28+5+-+t+%29+ ALIGN=MIDDLE  ALT=\"+240+=+%28+100+%2B+w+%29%2A%28+5+-+t+%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "-----------------------------<BR>\n" );
document.write( "(2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+240+=+500+%2B+5w+-+100t+-+w%2At+ ALIGN=MIDDLE  ALT=\"+240+=+500+%2B+5w+-+100t+-+w%2At+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "(2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+w%2At+%2B+100t+-+5w+=+260+ ALIGN=MIDDLE  ALT=\"+w%2At+%2B+100t+-+5w+=+260+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "(2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+t%2A%28+100+%2B+w+%29+=+260+%2B+5w+ ALIGN=MIDDLE  ALT=\"+t%2A%28+100+%2B+w+%29+=+260+%2B+5w+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "and,<BR>\n" );
document.write( "(1) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+240+=+%28+100+-+w+%29%2At+ ALIGN=MIDDLE  ALT=\"+240+=+%28+100+-+w+%29%2At+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "(1) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+t+=+240+%2F+%28+100+-+w+%29+ ALIGN=MIDDLE  ALT=\"+t+=+240+%2F+%28+100+-+w+%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Substitute this result into (2)<BR>\n" );
document.write( "(2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=++%28240+%2F+%28+100+-+w+%29%29+%2A%28+100+%2B+w+%29+=+260+%2B+5w+ ALIGN=MIDDLE  ALT=\"++%28240+%2F+%28+100+-+w+%29%29+%2A%28+100+%2B+w+%29+=+260+%2B+5w+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "(2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+240%2A%28+100+%2B+w+%29+=+%28+260+%2B+5w+%29%2A%28+100+-+w+%29+ ALIGN=MIDDLE  ALT=\"+240%2A%28+100+%2B+w+%29+=+%28+260+%2B+5w+%29%2A%28+100+-+w+%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "(2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+24000+%2B+240w+=+26000+%2B+500w+-+260w+-+5w%5E2+ ALIGN=MIDDLE  ALT=\"+24000+%2B+240w+=+26000+%2B+500w+-+260w+-+5w%5E2+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "(2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+5w%5E2+=+2000+ ALIGN=MIDDLE  ALT=\"+5w%5E2+=+2000+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "(2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+w%5E2+=+400+ ALIGN=MIDDLE  ALT=\"+w%5E2+=+400+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "(2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+w+=+20+ ALIGN=MIDDLE  ALT=\"+w+=+20+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "The wind speed is 20 mi/hr<BR>\n" );
document.write( "------------------------<BR>\n" );
document.write( "check answer:<BR>\n" );
document.write( "(1) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+240+=+%28+100+-+w+%29%2At+ ALIGN=MIDDLE  ALT=\"+240+=+%28+100+-+w+%29%2At+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "(1) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+240+=+%28+100+-+20+%29%2At+ ALIGN=MIDDLE  ALT=\"+240+=+%28+100+-+20+%29%2At+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "(1) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+240+=+80t+ ALIGN=MIDDLE  ALT=\"+240+=+80t+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "(1) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+t+=+3+ ALIGN=MIDDLE  ALT=\"+t+=+3+\"   DISABLED_style= \"max-width:90%; height:auto;\" > hrs<BR>\n" );
document.write( "and<BR>\n" );
document.write( "(2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+240+=+%28+100+%2B+w+%29%2A%28+5+-+t+%29+ ALIGN=MIDDLE  ALT=\"+240+=+%28+100+%2B+w+%29%2A%28+5+-+t+%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "(2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+240+=+%28+100+%2B+20+%29%2A%28+5+-+t+%29+ ALIGN=MIDDLE  ALT=\"+240+=+%28+100+%2B+20+%29%2A%28+5+-+t+%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "(2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+240+%2F+120+=+5+-+t+ ALIGN=MIDDLE  ALT=\"+240+%2F+120+=+5+-+t+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "(2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+2+=+5+-+t+ ALIGN=MIDDLE  ALT=\"+2+=+5+-+t+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "(2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+t+=+3+ ALIGN=MIDDLE  ALT=\"+t+=+3+\"   DISABLED_style= \"max-width:90%; height:auto;\" > hrs<BR>\n" );
document.write( "OK\r<BR>\n" );
document.write( "<BR>\n" );
document.write( "<BR>\n" );
document.write( "\n" );
document.write( " </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );